Shock absorber



Aug. 20, 1940. s. D. MITI-:Rl-:FF

SHOCK ABSORBER n Filed sept. 2o, 193e 6 Sheets-Sheet 1 Aug. 20, 1940. s.D. MITEREFF 2,212,426

SHOCK ABSORBER Filed sein. 2o, 19:58 e shuts-sheet 2 INVENTK SERGEI D.MITEREFF y ATTORNEYA UB- 20. 1940 l s. D. MITEREFF 2,212,426

SHOCK ABSORBER Filed Sept. 20, 1938 6 Sheets-Sheet 3 v INVENTOR. 5 ERGEID. MITER EFF ATTORNEY.

Aug. zo, 1941".

S. D. MITEREFF SHOCK ABSORBER Filed sept. 2o, 193s 6 Sheets-Sheet 4 AINVENTOR. SERGEI D. MITEREFF glp/w p1 Mmmm ATTORNEY.

A118- 20, 19ML s. D. MITEREFF SHOCK ABSORBER Fil'ed Sept. 20, 1958 6Sheets-Sheet 5 INVENTOR. SERGEx D. MITEREFF ATTORNEY.

Aug. 20, 1940. s. D. MITEREFF SHOCK ABSORBER Filed Sept. 20, 1958 6Sheets-Sheet 6 INVENTOR. SERGEI D. M |TEREFF 93h11 ATTORNEY.

Patented Aug. 20, 1940 PATENT OFFICE SHOCK ABSORBER Sergei D. Mitereif,Petersburg, Va., assigner of one-half to Elmon C. Gillette; New York,

Application September 20, 1938, Serial No. 230,764

23 Claims.

My invention relates to shock absorbers and has particular reference toshock absorbers employing elastic or other fluid and adapted to be usedwith automotive vehicles, trailers, etc.

'I'he object of ordinary shock absorbers is to reduce the recoil andoscillations of a body suspended on .resilient springs and having,therefore, a natural period of oscillations. 'Ihis is accomplished byabsorbing the energy of compression of the spring by internal frictionof a liquid which is forced to pass throughrestricted openings from onechamber of the shock absorber into the other, or, to a certain extent,by adiabatic compression of an elastic fluid. Such shock absorbers Workon the principle lof dash pots, offering but little resistance when therelative velocity of movement between the body and wheel is low, butprogressively increasing the resistance at higher velocities. An idealshock absorber Will dampen the movement of the body during the firsthalf of an oscillation thereby 4completely suppressing the periodicityof the body and spring oscillations. In practice, however, such a rapidenergy absorption will render the suspension very stiff with theresulting very rough movements of the body when traveling over roughroads. Some relief may be obtained by providing means to regulate therate of flow of the dampening liquid as, for instance, by having severalby-passes of different sizes which become successively operative atdifferent relative positions of the axles and the body of the vehicle,or by controlling the pressure of the dampening liquid and evenreplacing it by a compressible fluid. Attempts have been also made tocontrol the resistance to the ow of the liquid by inertia force of pilotweights attached to the body.

None of these arrangements of shock absorbers have been found fullysatisfactory. Themain 40 diiiiculty in bringing periodic oscillations ofa body under control and dampening them resides in the fact that thesuspension'springs are not supported on a1 xed foundation but move upand down as thewheels roll over uneven places on the ground. In order toobtain aperiodic oscillations under such conditions, the resistance tothe flow of liquid in an ordinary shock absorber must be increased tosuch an extent that the body would be compelled to follow closely themovements of the wheels in a series of irregular jolts in riding overrough spots. For this reason ithasbeen found impractical to try toobtain apcriodic dampening of oscillations and the shock absorbers areusually regulated so as to dampen oscillations more or less gradually.lThe result is (ci. zer-s) that the riding comfort is reduced becauseneither the rst jolt transmitted to the body every time the wheelsstrike an impediment on the road is decreased nor ensuing oscillationsare dampened aperiodically.

It may be noted that ordinary leaf springs pro- *duce a certaindampening eiect as a result of friction between the leaves, but thiseffect is unsatisfactory because of the abrupt reversal of direction ofsuch friction. Helical springs are more satisfactory in this respect. l

Ordinary shock absorbers do not solve the problem of properstabilization of,a moving vehicle,. also for the reason that they applydampening eiect equally and simultaneously to the body and to the axles,although the requirements of these elements are quite diiferent, notonly with respect to the magnitude and direction of dampening forces,but also to the time of their application.

It is" evident that the greatest degree of stabilization is wanted forthe body, and with an ideal stabilization or with an ideal shockabsorber the body Will remain practically at the same level in relationto the surface of the road in general; while the wheels with the axlemust be quite free to move up and down, following minor irregularitiesof the road, so that even at higher speeds of the vehicle the body willfloat smoothly in an approximately parallel alignment with the roadwhile the Wheels will move up and down over the irregularities of theroad surface. In order to approach such an ideal condition, a dampeningforce must be applied to the body in phase with and proportional toitsabsolute vertical velocity. Itis also desirable to apply a second forcewhich will be proportional to the vertical acceleration .of the body inspace. This second force, if applied in one direction, will have theefect of diminishing the natural force of inertia of the body so that itwill be possible to use a smaller dampening force for obtainingaperiodic stabilization.

If this second force is applied in the opposite direction it will havethe effect of increasing the natural inertia reaction of the body, thusconsiderably lengthening the natural period of oscillation of the bodyand decreasing its acceleration. The choice of the direction ofapplication of this corrective force is largely optional. As a generalrule. with light cars it may be desirable to increase the inertia whilelarge and heavy cars, busses etc.

"may require its decrease.

In practice the two forces can be combined together so as to obtain oneeiective force prowhere F is the stabilizing force, P--verticaldisplacement of the body, T--time, and K1, K1 are arbitrary constants ofadjustment.

" It should be noted that while in ordinary shock absorbers thestabilizing force is substantially vproportional to the velocity ofrelative displacement between the bor'y and the axle, in'my stabilizingdevice a force is applied to the body, which is proportional to theabsolute velocity and absolute acceleration of the body in space. It

is evident that this is a fundamental distinction which permits not onlyof a perfectly aperiodic dampening of the movements of the body but iteven tends to completely eliminate the original response of the body toroad shocks.

It should be pointed out that an ordinary shock absorber, even whenadjusted for very light dampening eiect, must'l necessarily'increase thevertical acceleration of the body when the wheels strike an obstructionand compress the springs. Thisvis because the direction of stabilizingforce and change in spring tension are coincident until the body startsovertravel or moves away from the wheel as a further result of theoriginal impact.

l With my stabilizing device 'the suspension springs can be made longeror shorter without materially affecting the riding comfort, the onlyrequirement being thatthe springs should have suiicient travel to clearordinary rough spots on the road. In fact, with certain adjustments mydevice can completely eliminate the springs.

In a typical practical embodiment of my invention I employ a combinationof` a piston and cylinder interposed between the body and'the springs orends of the front and rear axles, the cylinder having an upper and lowercompartment at the corresponding sides of the piston. It should be notedthat these compartments for convenience will be called upper and lowercorresponding to their positions in a vertical cylinder, although thecylinder with suitable operative connections, may be placed in anangular and even horizontal position or any other suitable uid operativemotor may be used instead of the piston and cylinder. I also providemeans to vary the diierence in the fluid pressure in the upper and lowercompartments in proportion to the vertical velocity and-acceleration ofthe body. For this purpose I provide a source of compressed uid,preferably air, and control its admittance to the cylinder by a suitablevalve actuated by a mechanism responsive to the vertical velocity andacceleration of the body. In order to obtain proportional regulation ofthe valve and to restore it into its neutral position, a valve operatingmechanism is provided responsive to the diierence in pressure betweenthe two sides of the 'of the body and the axle or, in othe words, itdoes not depend on the travel of the piston in relation to the cylinder;there is, however, provided a relatively small adjustment responsive tothe relative displacement of the body and axle in order to correctinaccuracies of the main controlling mechanism which may appear in time.

I also provide means to prevent the body from tilting over or rockingwhen the vehicle is rounding a curve at a more or less high speed. Forthis purpose I provide hinged weights which exert pressure on the valveoperating mechanism not only under action of vertical forces of inertiabut also under horizontally acting centrifugal force, the hinges beingpositioned so-as`to cause the valve on the outer side of the body tobuild up pressure above the piston for resisting downward movement ofthe body while the valve on the other side of the body will admit thecompressed air to the opposite side of the corresponding piston forkeeping the body down.

In a modified form my shock absorber can be used for stabilizing anaircraft in flight. It should be noted that an airplane in flight can beconsidered suspended in an elastic or even resilient medium, similarlyin certain respects to the spring suspension of an automobile. For thispurpose I provide my device with inertia elements responsive to angularindications but not responsive to vertical forces. Any angulardisplacement of a vehicle, therefore, will cause thelvalve to move;thereby admitting compressed air into the cylinder and causing thepiston to move. This movement will be transmitted to the ailerons on thewings in a proper direction so as to restore the horizontal position ofthe airplane. The pressure of air stream on the ailerons will bebalanced by the pressure on the piston, the valve being restored intothe neutral position by the diierential pressure -on the side of thepiston.

It is obvious that my invention may be embodied in more oi' lessdifferent forms as it will be apparent in the accompanying specificationin which certain typical embodiments are described and illustrated, inthe drawings as follows: Fig. l is a sectional elevational view of myshock absorber and stabilizer taken at the line l-l of Fig. 2.

Fig. 2 is a sectional View of the same taken on the line 2-2 of Fig. 1.

Fig. 3 is a sectional elevational view of a modliied shock absorber.

Fig. 4 is a top plan view of the shock absorber shown in Fig. 3. Fig. 5is a diagrammatic view oi my shock absorber with a source of compressedfluid for its" operation.

Fig. 6 is a vfractional sectional elevational view of a modied shockabsorber.

Fig. 7 is a sectional elevational view of another modification.

Fig. 8 is a detail view of a modified inertia responsive part of myshock absorber.

Fig. 9 is a top plan view of the same.

Fig. 10 is a detail view of another modication of the inertia responsivepart.

Fig. 11 is a top plan view of the same.

Fig. 12 is an elevational view of a modified stabilizer as applied tothe operation of airplane ailerons. Fig. 13 is a diagrammatic view of anelectroy magnetic shock absorber.

Fig. 14 isa fractional detail view of an airvalve forming a part of theapparatus shown in Fig. 1. 75

Fig. 15 is an end view of a detail shown also in Figs. 10 and l1.

One embodiment of my invention is shown in Figs. l, 2 and 14 andconsists of a hollow cylindrical casing I with a closed outer end 2 andan open inner end with a flange 3 to which a fiat cover 4 is attached bybolts 5.

'Ihese bolts are also used for attaching the casing I to a frame 6 of avehicle such as an automobile, etc. An impeller having a hub 1 and vanes8 is rotatively fitted in the casing I for which purpose "it hastrunnions 9 and I0 journaled in the cover 4 and end portion 2respectively. The trunnion I has a. splined extension I I fitted in asplined hole in anarm I2 tightened on the extension I I by a nut I3. Theend of the arm I2 has a. ball I4 rotatively clamped in the end of atubular link I5 (Fig. 3). The other end ofthe link I5 engages a ball I6on the end of a rod I1 extending from an axle I9 of the vehicle,preferably suspended from the frame 6 on suitable springs I8 showndiagrammatically in Fig. 5.` The arm I2 therefore moves with the axle I9when the springs I8 are flexed one way or the other when the vehiclemoves over a more or less rough road, the relative movement between theaxle and the frame 'resulting in the rotation of the impeller in thecasing. The blades 8 have an air tight fit in the casing I and may beprovided with a suitable packing (not shown). The casing I has inwardlyextending stationary varies interposed between the impeller varies 8.The stationary vanes also form an air-tight sliding t in the casing Ithereby forming air-tight chambers 2I and 22. The impeller, with theoasing therefore forms a compressor for 'a iiuid such as air which maybe placed in the chambers 2| and 22. The device can also operate as amotor when a fluid is delivered under pressure into the chambers 2l, forinstance, while exhausting the iiuid from the opposite chamber 22.Chambers 2l have ports 23 'in communication with each other throughducts or holes 24 and 25 bored in the end wall of the casing I, and inan enlarged portion 26 of the casing I. Similarly the chambers 22 haveports 21 in communication with each other through ducts or holes 28 and29. The holes and 28 are in communication with a cylindrical valvechamber 38 through ducts 3l and 32.

The valve chamber 30 is closed at the bottom and at the top by covers 33and 34. The latter cover has a hole for a rod 35 having valve discs 36and 31. These discs form an inner valve sliding in an outer tubularvalve 38 which in turn slides in the valve chamber 30. The lower end ofthe tubular valve 38 has a bottom plate 39 to which a plunger 40 of adash pot 4I is attached the latter being fastened by a bolt or screw 42to the cover 33. The dash pot attachment tends to retard the movement ofthe tubular valve 38, the dash pot being filled with oil. Springs 10 and69 press against the bottom plates 39 and 45 yieldably retaining thevalve in the central position.

. The valve chamber 30 has annular grooves or recesses 46, 41, 41', 48and 48' in communication with the inside. space of the sleeve valve 38through ports 49, 50, 5I and 5I'. The groove 46 opens into a pipe 52extending from a tank 53 (Fig. 5) with a safety valve' 54 for acompressed air or similar fluid. The tank 53 is connected by a pipe 55with an exhaust port 55' of an air compressor 56, with a. pistonconnected to a shaft 51 through an eccentric 58. 'I'he shaft 51 may beoperated by an engine or auxiliary motor (not shown). A check valve 59is placed in the pipe 55 and prevents the reverse air flow from thetank.

In order to relieve the compressor when there is sufficient pressure inthe tank 53, an unloading valve 60 is provided in a pipe 6I to theintake port 62 of the compressor 56. A plunger 63 keeps the valve 60open under Ypressure of a spring 64. When the pressure in the tankrises, however, to a certain point, the plunger 63 is moved upwardagainst the tension of the spring, closing the intake for the compressorand thereby unloading the latter.

The groove 41 is connected by a duct 65 with the duct 25, the groove 41'being connected with the duct 29 by a duct 6B. 'I'he ducts 48 and 48'are opened to the outside air through nipples 61 and 68 which may bethreaded as shown for connection with an air filter or similar device(not shown), or el'se with a vacuum tank, if vacuu operation ispreferred.

The valve discs 36 and 31 normally keep the ports 50 and 5U'closed, thesleeve valve 38 being kept in the neutral or middle position by springs69 and 10. The sleeve valve remains in the neutral position as long asthe air pressure on both ends remains the same. A slight difference inthe exposed end surface can be taken care'of .by adjusting the lowerspring 10 for less compression than the upper spring 69. One of theobjects of this arrangement is to relieve anypressure which may be builtup in the compartments 2l or 22 when the arm I 2 is moved up or down inrelation to the casing I. Thus, for instance, if the arm I2 is movedupward, air in the compartments 22 will be compressed with the creationof corresponding vacuum in the compartments 2I. As a result, there willbe differential pressure on the ends of the sleeve valve 38, causing thelatter to move upward against the pressure of the spring 69. The port 58will be then uncovered into the inner chamber of the sleeve valve incommunication with the port 43, thereby admitting compressed air intothe compartments 2| and compensation vacuum created therein. The port 50will be at the same time moved vaway from the disc 36 and uncoveredbeing brought into communication with the port 5I' and allowingtherefore the air from the chambers 22 to escape into the atmosphere.The pressure in the chambers 2I and 22 will be thus equalized and thesleeve valve brought back into the neutral position. Similarequalization will take place when the arm I2 is moved downward so thatthere will be no resistance for the movement of the arm I2l as long asthe valve discs 36 and 31 remain stationary.

The object of the disc valve assembly 35 and 31 is to control admissionof the compressed air into the compartments 2l and 22 so as to lof, awell 14 tted on top of the casing I and attached with screws 15. Thewell is filled with a suitable relatively incompressible liquid 14' suchas colloidal mixture of oil and sulphur, mixture of glycerine andalcohol, etc. It has a cylinder 16 fitted in its bottom portion with aplunger 11 having flexible bellows 18 attached to the lower end of thecylinder and forming an annular chamber, the liquid in communicationwith the well 14 through vents 18'. A rod 18" extends from the plungerand has a pivot 18 connection with a lever 80. The top of the cylinderis closed with a cover having apertures 8| for admitting the liquid inand out of the cylinder, thereby causing the plunger to move up anddown.

A second cylinder is provided in the well having flexible or collapsiblewalls 82 and a top plate 83, the latter serving as a plunger, a rod 84extends from the plate 83. A compression spring 85 keeps the plungerplate 83 in the raised position. The tension can be adjusted by a cap 86threaded on the end of the cylinder. The cap is retained in its adjustedposition by locking a set screw 81 tted in the wall of the well. Theother end of the rod 84 is pivoted at 88 to one end of the lever 80. Oneor the other of the pivots 18 an'd 88 form, therefore, a fulcrum for thelever 88 depending on which plunger is moved. The other end of the leverlis connected to the end of the valve rod 35 as by a pin 8| engagingelongated slots in the formed end of the lever 80.

The operation of my shock absorber is as follows:

As long as the vehicle equipped with my shock absorbers travels on asmooth surface, the weight of the body will be balanced by theresistance of the springs over the wheels. Oil 14' or other suitableliquid in the well 14 will be under normal pressure from the weight 1|,the valve discs 38 and 31 and the sleeve 38 being then in the neutralposition with both ports 50 and 58' closed. The air pressure will beequal at both sides of the piston vanes 8 or in chambers 2|- and 22. Ifthe vehicle, or one of its wheels, will encounter a raised spot, stone,etc., on the road, the wheel will rise in passing over the obstacle,compressing the spring before the inertiaof the body is overcome. Thearm |2wil1 be turned by the rising axle causing movement of the pistonvaries 8. As a result; air in the chambers 22 will be compressed andcorrespondingly expanded in the chambers 2|. As soon as an appreciabledifference in pressure is built up, however, the sleeve valve 38 will bemoved upward, as it was explained before, its lower end being incommunication with the now compressed air in the chambers 22 throughducts 32, 29 and 28, the upper end being in communication with theexhaust side 2| of the piston vanes, ducts 3|, 25 .and 28. The sleevevalve will open the port 58 admitting compressed fluid from the pipe 52into the chamber 2| and the port 58 will also be opened permittingescape theroad are relatively slight, resulting in a very soft ride withpractically no resistance added to the action of the vehicle suspensionsprings.

If the prominence on the road is such, however, that the springsupporting the body above the wheel is appreciably compressed, theincreased spring tension will tend to lift the body with the upwardacceleration. This will cause the weight ll to exert pressure on the oil'le' in the reservoir This operation will be repeated with the' 14. Thetotal travel of the weight being small, its pressure will beproportional to the acceleration of the body due to the downward inertiareactiveforce of the weight. Pressure will be transmitted through theoil to the vpistons 11 and 83. Its eect on these pistons will bedifferent, however, since the movement of the piston 83 is resisted bythe compression spring 85, while the movement of the piston 11 isretarded because the oil must pass to the piston Athrough the apertures8|. The travel of the piston 11 will be, therefore, in delayed phaserelation to the travel of the piston 83 so that the latter will have atendency to move rst thereby slightly raising the valve rod 35 while thepiston 11 has not yet moved. This eifect, however, will be of relativelyshort duration since the apertures 8| are relatively large and thespring is relatively strong, so that the valve 35 will begin almostimmediately to move downward under the predominant action of the piston11 which isresponsive to the upward velocity of the body.

The valve rod 35 when moving downward, opens the port 50 therebyadmitting compressed air from the pipe 52 into the chamber 2| throughthe ducts 65', 25 and 24 and ports 23. The port 50 will be also openedconnecting the chambers 22 with the outside air through the ports 21 andducts 28, 29 and 8G. The dilerence in pressure thus established betweenthe chambers 2| and 22 will be communicated to the opposite `ends of thesleeve valve 38, causing the latter to follow the valve 35 and to movedownward to a distance equal to the displacement o f the valve 35thereby closing the ports 50 and 58,'. If there is any leakage of airbetween the chambers, it will cause the sleeve 38 to move slightlyupward thereby reestablishing the difference in pressure. Since thesleeve 38 is centered on the springs 69 and 10 the air pressurenecessary to move it in accordance with the movement 'of the valve 35will increase with the compressori of the springs and will beproportional to the downward travel of the valve 35, which isproportional to the upward velocity of the body less its acceleration.The upward (clockwise on the drawings) torque of the air pressure on thepiston vane 8 is also proportional to velocity of the body minusacceleration. 'This torque is transmitted to the axle i9 by the arm I2in the upward direction and, therefore, -to the body in the downwarddirection, thereby restraining the latter from following the axle andfrom moving upward. It should be noted that in my system the valvesreverse. the air pressure which normally should be developed in'chambers2| and 22 under action of moving vanes 8.

The upward movement of the axle will cease when the wheel reaches thetop of the elevated spot on the rod- If the elevation. continues forsome distance, the body will gradually adjust itself to the new positioninA space above the axle, i. e. it will reestablish the normal elevationabove the axle, such a movement will take place without overtravelingand, therefore, aperiodically, without subsequentoscillations. This isdue to the fact that the valve -35 will remain in downward position fromthe neutral as long as the body has a tendency to move upward andtherefore the differential air pressure on the `Xvanes 8 will restrainthe body from moving upward, the releasing action-taking place graduallyand without overtravel on the part of the body.

If the wheels move downward, the body will have va tendency to followthem in the downward 7g direction, thereby causing the weight 1| toexert inertia reactive force in the upward direction,

' reducing the oil pressure in the well 14 and causingfthe pistons 83and 11 to move upward. The valve 35 will move upward, admittingcompressed air into the upper chambers 22 and restraining thereby thedownward movement of the body. The operation in all other respects willbe similar to the already described operation when the Wheels moveupward.

The plunger rod 18" has a substantially constant loading pot consistingof a plunger 89 moving in a pot or cylinder 90. The latter is connectedby a duct 99 with a chamber 92 in which slides a cylindrical valve 93. Ashock absorbing element is also connected with the chamber consisting ofa cylinder 94 with a plunger 95 resting against a compression spring 96.The plunger acts as a buffer, moving inwardly when there is a suddenrise in pressure in the chamber 90. The valve 93 has an annular recess91 (see also Fig. 14) in communication with the chamber 92 by means ofvashort duct 91'. The front end portion of the valve covers an annulargroove 98 connected with the pipe 52 by a duct 9|.' The.

rear valve portion closes an annular groove |00 connected with theoutside air through a duct I 0I. A helical compression spring |02 keepsthe valve in its neutral position as shown, the spring resting against asliding block |03 with a roller |04 resting against an eccentric |05 on"the shaft I0. The eccentric is positioned so that it rests with itsmiddle portion against the roller when the arm I2 is in the middle orneutral position. The eccentric moves the block from center of shaft I0when the arm I2 is raised and lets the block slide back when the arm |2is lowered. At the extreme limits of movement of cam |05 it is providedwith raised portion 30| and a depression 300 in order to preventexcessive travel of the wheels whenencountering unusually bad roadconditions.

In the first case the spring moves the valve out until the groove 98isuncovered, admitting compressed air from the pipe 52 into the chamber92 and through the duct 98 with the cylinder 90. This'retards anyfurther movement of the plunger 11 without affecting the plunger 83. Asa result, the movement of the valve 35 will be reversed. 'Ihe movementof the valve 93 will be stopped and the valve moved back into theneutral position when the pressure in the .chamber 92 compensates thepressure of the spring |02. It is evident that greater air pressure willbe maintained in the cylinder 90 for greater upward deections of the armI2. The reverse takes place when the arm I2 is moved downward, the valve93 moving then inward and opening the groove |00 into the atmosphere andthereby reducing pressure in the pot cylinder 90. In this way a constantaverage distance is maintained between wheels and body. The desireddegree of averaging delay between pressures in duct 92 and duct 99 beingcontrolled by plug 92' partially closing duct 99.

A modied device is shown in Figs.'3 and 4. A cylindrical casingl |00 isattached to the frame 0 of the vehicle by bolts 5 and has covers |01 and|09 attached to the casing by bolts |09. A piston or plunger I I0 slidesin the bore IIO' of the cylinder and has a rod II| sliding in anair-tight gland I|2. The other end of the rod III is pivoted at I|3 to abar II4 having a ball Mat the end engaged by a ball-shaped bearing in atubular rod II mounted on the axle I9 of the vehicle.

The other end of the bar ||4 is pivoted at I|5 to a supporting link IIBpivotally connected at ||1 to a lug |I8 on the cover |01. The casing|06has an extension II9 with a cylindrical bore for a stationary sleeve|20. The latter has end 5 walls |24 and |22 lwith bearings for the stemof a sliding valve |23. Air chambers |24 and |25 are formed at the endsof thesleeve |20 and are connected with the cylinder bore I|0' by ductsI 21 and |26. The stem of the valve |23 is of an en- 10 larged diameterat the top where the stem passes through the end |22 in order toequalize the air pressure on both ends of the stem.'

This is accomplished by making the area of the shoulder at the enlargedupper portion of the 15 stem equal to the area of the lower end portion.The valve has valve discs 36 and 31 closing ports 50 and 50 when in theneutral position. These ports are in communication with ducts |29 and|28 extending to the upper and lower ends of the 20 cylinder bore I|0'.The ducts terminate at a distance from the end covers |01 and |08 inorder to provide a dead space for the air at the end of the pistontravel so as to form a shock absorbing buier between the piston and theend covers. 25

Exhaust ports 5| and 5I are also provided in the sleeve |20 incommunication with the exhaust ports |30 and |30.

The upper end of the valve stem |23 has an enlarged portion |3I to'whichone end of a spring |32 is attached. The other end of the spring isattached to a lever |33. The spring thereby serves as a connecting linkbetween the valve stem |23 and the lever |33, working both oncompression and tension. oted at |34 on a standard |35 mounted on thecover |08. Blocks or weights |36 and |31 are slidably mounted on theends of the lever-|33. The weight |30 is made larger and heavier thanthe weight |31 and their relative positions can be 4^ adjusted by nuts|38 threaded on the ends of their lever |33.

The valve |23 may be displaced from the neutral position by 'adifferential pressure in the end chambers |24 and |25 which may becaused 45 by the displacement of the piston I I0 in the bore I l0. Itcan be seen that such a displacement of the valve will result in theequalization of the `air pressure at the opposite sides of the piston,

the effect being similar to equalizing action of the 50 sleeve 38 inFig. 1.

Thus if the piston |I0 is moved upward, for

instance, compressing air in the upper portion of on a bracket |42supported on the cover |00. A

small regulating weight |42' is adjustably fitted on the other end ofthe lever. The lever |40 engages the enlarged portion ISI, tending tolift the stem |23 under action of the larger weight 'The necessaryretarded action for the velocity component is obtained by connecting anoil dash u The lever |33 1s piv- 35 'he pressure on both 00 The inertiacomponent is 5 por to the lever las. 'rnedasn poils represented by aexible cylinder |83 with an upper cover |88 having a clevis |85 pivotedat |86 to the lever |33. A middle wall |61 is tted in the cylinder andis provided with a small aperture |63 Afor allowing oil, or similarliquid, to pass between the lower and upper compartment of the cylinder|53.

The wall or diaphragm |31 extends outside the` .a second rod |53extending outside the casing and resting against an arm |58. The latteris pivotally supported at |55 in a bracket |58 extending from the lowercover |61 oil the casing. the other end being pivotally connected at |51to one end of a link |58 whose other end is pivoted at |59 to the leverH8. rIhis arrangement is equivalent to the eccentric regulated dash pot69, 60 of Fig. 1. An upward movement for instance, of the frame 6 orbody of the vehicle, will result in the downward movement of the weight|86, forcing the oil from the upper portion of the cylinder M3 throughthe aperture |68 into the lower portion against the pressure ofthe'spring |52. The resistance of the spring will be increased as thepiston moves upward and will correspondingly decrease for its downwardmovement.

A modified device' is shown in Fig. 6. The main portion of the apparatusis similar to the one shown in Fig. 1 with the exception that a shelf|60 is provided on top of the casing ||5| for the enlarged base |62 of arelatively tall tube |63 with a cap |68 on top. A weight |65 slides inthe tube and is supported on the end oi a long compression spring |66whose other end rests on a partition |61 at the lower end of the tube.The partition supports an inner tube |68 serving as a dash pot inconnection with a plunger |69 mounted on the ends of a rod |10 extendingfrom the weight block |65. An aperture |1| allows thecarries anadjustable, fitted weight |36, the' other end of the lever carrying a,smaller weight |16 adjustable fixed by a'set screw |11. The middleportion ofthe lever |15 rests against the under side of the disc |13,the end of the lever being pivotally connected at |18 to a rod |15having a plunger 89 at the end.

With-this device in operation, Awhen the vehicle reaches an elevatedspot on the road, the body suspension springs will begin to becompressed. 'Ihe iirst tendency of the body to go down will be overcomeby the compression of the springs with the result that the body willhave a 'tendency to move upward. The weight |85, being sup ported by along spring |66 of an almost constant resistance, will have a tendencyto remain stationary in space by inertia. The casing 86| will moveupward, compressing the spring |86 andV 'upward through the orifice |1|.

aaiaeee causing the piston |68 to move in the dashpot |68, forcing theliquid in the dash pot to move The oil pressure in the dash pot may bemade very small in comparison to the force of inertia of the Weight |86and therefore, the resistance of the dash pot will have only a verysmall effect on the weight except that it will inhibit its oscillations.

The oil pressure under the piston created by the upward movement of thebody will be prof portional in magnitude to the rate of relativeAdisplacement between the weight |65 and the casing |6| and will be,therefore, proportional to the absolute velocity of the body 'in space.

A relatively weak tension-compressionspring |12 under the piston |69will produce a downward force -on the bottom of the dash pot which forcewill be proportional to the absolute vertical dise placement of thebody. 'I'he weight |36 will move with the body and will generatedownward reaction yforce proportional to the absolute accelera tion ofthe body in space. This force is trans mitted to the bottom of the dashpot as in upward thrust because the support is located between theweight and thev dash pot.

It will be seen, therefore, that the bottom |13 of the dash pot which is`attached to the valve |23 will be subjected to three forces: one,proportional to the vertical displacement of the car, anotherproportional to the velocity of displacement of the body, and third,proportional to the acceleration of the body.

The mechanism maybe made and adiusted so that the first two forces willbe greater than y the third so that the net force acting onl the vlave|23 will be in downward direction, so that the valve |23 will movedownward to a small distance thereby admitting compressed air into thecham# bers 2|, releasing air from the chambers 22. y

The torque thus created and applied to ythe piston vanes 8 will betransmitted by the arm |2 as an upward force to the axle and as adownward force to the body. In view of the fact ,that the valve |23 inthe form of pistons subjected to the diierence in air pressure betweenthe chambers 2| and 22 through ports 3| and 32 the air pressure willtend to bring the valve back into the neutral position as soon as thedifference in air pressure will reach value proportional to the downwardforce created by dash pot spring |12 and inertia of the weight |36.

It will be apparent. therefore, that the operating force of the arm I2will resist against the up. wa/rd movement of the body under action ofvthe increased compression of the car springs caused by the elevation onthe road. If instead of elevation,` the vehicle'will encounter adepression, the body will have a tendency to move downward and theforces will be reversed so that the arm |2 will have a tendency tooppose the downward movement of the body. Air vents |86 may be providedin the upper end of the tube |58.

A modified form of my stabilizer is shown in Fig. 7. A cylinder |8| hastop and bottom covers |82 and |83 respectively and an outer cylindricalcasing |88 spaced from the cylinder |8| so as to form an annularclearance |86.- A cylindrical sleeve valve |86 is tted in the clearance|85 .and

has inner circular ribs |81 and |81 closing ports |88 and |88 in thewalls of the inn'er cylinder.

The outer peripheral side of the sleeve |86 slidr ably bears against theinner surface of inner circular ribs |88 on the outer casing ,184. The

valve |88 has ports |80, |9| and |9|' in communication with the intakepipe7 52 for the compressed-fluid and exhaust ports |30 and |30respectively. The sleeve valve |86 has plungers |92 at the bottom andsimilar plungers |93 at the top sliding in corresponding bores |94 and|94' in communication with the respective ports |88 and |88' throughducts |95, and |95. The upper plungers are of a larger diameter, havingrods |96 extending through the top cover |82, the exposed areas oftheplungers being substantially equal. The rods |96 are attached to theends of a bar |91 connected at the middle point |98 to the lower end ofthe spring |12. The sleeve valve |86 is thereby balanced in the neutralposition and is moved one way or the other by differential'air pressurein the end portions of the cylinder. The acceleration responsive memberin this case consists of the weight of the valve |86 itself and itsinertia force is 'additive to velocity component of dash pot |68.

The ports 88 and |88' are spaced from the ends of the cylinder in orderto provide for a cushioning effect by the air trapped by the piston |0at the end of its travel in either'direction. The object of thisparticularconstruction is to provide a very large area of ports for thecylinder in order to eifect more rapid action of the valve in admittingcompressed air into the cylinder. s

My device with its inertia control of compressed air effectivelyinhibits movements and oscillations of the body in response to thecorresponding movements of the wheels and axles. My device can be alsoadapted for preventing turning or upsetting effect on the body as may becaused by the centrifugal force when the vehicle is rounding a curve ata high speed. This arrangement is shown in Figs. 8 and 9 and consists inthe provision of Weight 200, the latter having arms 20| rigidly attachedto the sides of the weight as by vscrews 20|', the other ends of thearms being pivotally mounted on shaft 202 supported in brackets 202' ona double ring 203 clamping diaphragms 204 and 205 to a flange 206 of anoil well 201. The latter is separated by a partition 208 formingseparate compartments 209 and 2 l 0 for the velocity responsive element11 and for the inertia. responsive element 83. The weights bear on thediaphragms 204 and 205. The arm 20| is positioned in direction at rightangles to the longitudinal axis of the vehicle and in oppositedirections for the right and left side of the vehicle so that the shaft202 is placed on the inside and the weights on the outside withreference to the central longitudinal axis of the vehicle. The weightsare, therefore, free to respond to vertical forces of inertia but, atthe same time, weight. 200 also responds to the centrifugal force whichcreates a turning moment for the weight around its pivoting points.. Itfollows, therefore, that the centrifugal force creates a turning momentfor the weights located at the outer side of the vehicle in rounding acurve thereby :producing a reaction force by compressed air tending tokeep this side of the vehicle up with a force which may be madesuillcient to overcome the pressure on the springs caused by the turningmoment of the centrifugal force on the body of the vehicle. There willbean opposite effect on the weights at the-inner side of the vehicle.the turning moment being in this case such as to raise the weight fromthe diaphragms.

A similar arrangement is shown in Figs. 10, 11 and 15 illustrating amechanism such as shown in Fig. 3 with the exception that the inertialever |40 is placed at right angles to the velocity lever |33 and has aweight 2|| extending vertically so as to be affected by horizontalforces of inertia in the same manner as the weight 200.

Another modification is shown in Fig. 12, this form of the stabilizerbeing adapted for either lateral, longitudinal or directionalstabilization of an airplane. For this purpose this stabilizer isdesigned to respond only to rotary motions in a plane transverse to thedirection of flight for lateral stabilization, or in the vertical planeof flight for longitudinal stabilization, or also in the horizontalplane of iiight for directional stabilization. g

This device has weights 2 I2 and 2|2' which are equal in this case andspaced at the same distance from the pivotal support on an arm |33. Theforce transmitted to the dash pot |43 is proportional to the angularacceleration of the airplane if the device is placed on its axis ofrotation. 'I'he device is not responsive, however, to straight linearmotions. Therefore the distance (which is made purposely small)transversed by weight 2|2 is proportional to the angular velocity. Theforce of spring |32 is, therefore, also proportional to angularvelocity.

Similarly Weights 2|3 and 2|3' are of the same size and spaced on an arm|40 at the same distance from the pivotal support |4| so that the forcetransmitted to the valve |23 is proportional to the angularacceleration. The total net force on *he valve is therefore,proportional to the ang .lar velocity plus or minus angular accelerationof the airplane. This force is balanced at all times by the differentialpressure acting on the piston ||0 since the ends of the valve areexposed' to this pressure through the ports |26 and |21 (Fig. 3).Consequently at any given moment the differential pressure will beproportional to the angular velocity plus or minus angular accelerationof the airplane, independently of the position of the piston ||0 in thecasing |06. The

piston rod is connected by an arm 2|4 with a vcable 2|5 guided byrollers 2|6 and connected with ailerons (not shown), elevators (notshown) or other control devices which introduce reaction between theairplane and the surrounding air in direction required for stabilizingthe airplane or straightening its position. Under the force of airpressure on piston ll0'the ailerons Will move such a distance as toreach a balance between the force on the piston and the force or torqueof the air stream acting on the ailerons (elevators, rudder etc.). Thestabilizing torque of the latter will be therefore, proportional to thedynamic characteristics of the angular motion of the airplane around itsaxis of rotation.

vIn another embodiment of my shock absorber as shown in Fig. 13electromagnetic forces are utilized for producing stabilizing reactionon the body. A heavy magnet 2| 1 is suspended on a long spring 2|8attached to the body 6 so that it has a tendency to remain stationary inspace due to its inertia, moving therefore in relation to a coil 2|9which is also attached to the body 6.

Voltage generated in thecoil 2|9 by the movement of the magnet istherefore proportional to the vertical velocity of the body. A weight220 rests on a compression rheostat or piezo-crystal 22| and movestogether with the body. The resistance of the rheostat or electromotiveforce of crystal varies, therefore as a vertical acceleration.

A vacuum tube amplifier 222 is connected with the coil and therheostatand amplies the currents, using a source of current 223 and designed tomake its output proportional to the sum or difference of the verticalvelocity and acceleration of the body. The amplifier 222 can be also ofdiierentiating or integrating characteristic.

The output of the amplifier 223 is fed into a led coil 221 of a constantspeed D. C. generator 22d which, therefore, generates voltageproportional to the dynamic characteristics of the vertical movements ofthe body.- The armature of the generator is connected to a coil 225attached to the body. A magnet 226 attached to an axle I9 is moved inthe coil 225 being either attracted or expelled depending on thedirection of current through the coil, the force of such attraction orrepulsion being proportional to the current through the coil, so thatthe stabilizing force of the magnet Will be proportional to the verticalvelocity and acceleration of the body.

In order to minimize the eiect of counter electromotive force generatedinthe coil by the movements of the magnet', `a feed-back connection isprovided for the ampliiier, thelatter being designed to vary current inthe solenoid accordingly so as to suppress the eiiect of the C. E. F.'I'his feed-back connection can alternately be made to response to theextent of relative movement between coil 225 and magnet 226. In this waya purely magnetic suspension. of the body to be stabilized can` beachieved. If the output of amplifier 222 is fed directly into vcoil 225such a rapid response to movements of body 6 can be obtained as topermit a stabilization of body against even high frequency oscillationsdue to sound transmission from i9. This kind of stabilizer or noisecounteracting device is particularly applicable to street cars due toreadily available source of electric energy. L

I claim as my invention:A

l. A shock absorber and stabilizer for a body adapted to have a motionof1translation`over a supporting medium, comprising a casing, a membermovably supported in the casing and separating the casing into upper andlower chambers, a source jof compressed fluid, means to selectivelyadmit the fluid into one of the chambers simultaneously exhausting theuid from the other chamber, thereby creating a difierential pressure inthe chambers, means to interpose resistance between the body and thesupporting medium by said diierential pressure, and means to` controlthe differential pressure in proportionto the velocity andaccelerationof the movements of the body transverse to the motion' of translation.

2. A shock absorber and stabilizer for a body adapted to have a motionof translation over a chamber, thereby creating la differential pressurein the chambers, means to interpose resistance between the body and thesupporting medium by said differential pressure, a movable elementresponsive to dynamic characteristics of' 4the movements transverse tothe motion of translatlon, and means to control the differential presf@sure by the element so as to make this differential pressurecontinuously-proportional to a combination of said dynamiccharacteristics.

n 3. .A shock absorber and, stabilizer for a bodyresilientlysupportedlon a member contacting a supporting medium,-comprising a motor inter-- posed between the body and the member, a

motion of translation' on the supporting medium, a movable elementadapted to control the power vfor the motor, and means responsive to thevelocity and acceleration of the body in direction transverse to itsmotion of translation, for controlling the movable element, so as tocause the motor to resist the transverse movement of the body.

4. A shock absorber and stabilizer for a body resiliently supported on'amember contacting a supporting medium, the body and the member beingadapted to have a motion of translation over the supporting medium, thebody being adapted to have oscillatory movements in relation to thesupporting member in direction transverse to the motion of translation,a fluid motor interposed between the body and the member, a source ofcompressed iiuid for the motor, a movable element responsive to dynamicproperties of the transverse movements of the body, a valve adapted toadmit the ud into the motor, and means to move the valve by the movableelement so as to oppose the transverse movements of the body by themotor by the compressed fluid.

5. A shock absorber and stabilizer for a body resiliently supported on amember contacting a supporting medium, the body and the member beingadapted to have a motion of translation over the supporting medium, thebody being adapted to have oscillatory movements in relation to thesupporting member in direction transverse to the motion of translation,a fluid motor interposed between the body and the member, a source ofcompressed fluid for the motor, a valve controlling admittance of theiiuid to the motor, a movable element responsive to dynamic -propertiesof the transverse movements of the body, and means to move the valve bythe movable element so as to oppose the transverse movements of the bodyby the motor, and means to return the valve into the neutral position bythe operative uid pressure in the motor.

6. Av shock absorber and stabilizer for a body resiliently supported ona member contacting a supporting medium, the body and the member beingadapted to have a motion ofA translation over the supporting medium, thebody being adapted to have oscillatory movements in relation to thesupporting member in direction transverse to the motion of translation,a iiuid motor interposed between the body and the member, and consistingof a casing with a plunger movably fitted in the casing and separatingthe casing into the upper and lower chambers, a source of fluid for themotor, a valve adapted to control the adrnittance of the fluid into oneof the chambers neutralize the action of the valve by the differentialpressure in the chambers.

'7. A shock absorber and stabilizer for a body resiliently supported on'a member contacting a supporting medium, the body and the member beingadapted to have a motion of translation over the supporting medium, thebody being adapted to have oscillatory movements in relation tothechamber, a movable element in the casing responsive to the velocity ofthe transverse motion of the body,` a movable element in the casingresponsive to the inertia of the body in its transverse movement,meansto operate the valve by said movable elements so as to oppose thetransverse movements of the body while assisting movements of thesupporting member, means to neutralize the action of the-valve by thedifferential pressure in the chambers, and means .to vary the effect ofthe differential pressure on the valve in l accordance with the relativeposition of the plunging and separating the the supporting l the inertiaof er in the casing.

8. A shock-absorberA and stabilizer for a body resiliently supported ona member contacting a supporting medium, the body and the member beingadapted to have a motion of translation over the supporting medium, thebody being adapted to have oscillatory movements in relation to thetween the body and the membeigand consisting of a casing with a plungermovably fitted in the cascasing into the upper and lower chambers, asource oi' compressed fluid for the motor, a valve adapted to controlthe admittance of the fluid into one of the chambers while exhaustingthe iluid from the other chamber, a movable element in the casingresponsive to the velocity of the transverse motion movable elements onthe valve in accordance with the relative position of the plunger in thecasing.

9. A shock absorber and stabilizer for a body resiliently supported on amember contacting a supporting medium, the body and the member Jeingadapted to have a motion-of translation over medium, the body beingadapted to have oscillatory movements in relation to the supportingmember in direction transverse to the motion o1' translation, a fluidmotor interposed between the body and the member, and consisting of acasing with a. plunger movably fitted in the casing and separating thecasing into the upper and lower chambers, l:a source of compressed fluidfor the motor, a valve adapted to control the admittance of-the `fluidinto one oi the chambers while exhausting the uid -from the otherchamber, a movable element in the casing responsive to the velocity ofthe'transverse motion of the body, a movable element in the casingresponsive to the y in its transverseimovement, means to operate thevalve by said movable elements so as to ments of -the body whileassisting movements of the supporting member, and means to neutralizethe action of the valve by the differential pressure in the chambers, anauxiliary uid motor opposing movement of said elements, and means tofluid into one of the chambers while exhausting the fluid from the otheroppose the transverse movecontrol the auxiliary motor by the position ofthe plunger in the casing.

10. A shock absorber and stabilizer adapted t0 be supported between thebody and the axle of a vehicle and comprising a casing and a membermovably fitted in the lcasing separating the latter into the upper ofcompressed fluid for the casing, a valve controlling the admittance ofthe iiuid into the chambers of the casing, means to place the valve intothe neutral position by the differential pressure in the chambers, saidmeans being inoperative for the extreme positions of the members in thecasing, elements on the casing responsive to the velocity and/oracceleration of the body in directions transverse to the axis of thevehicle, and means to operate the valve by said elements so and lowerchambers, a source as to produce differential pressure against themovable member opposing the transverse movements of the body whileremoving resistance to the corresponding movements of the axle.

11. A shock absorber and stabilizer adapted to be supported between thebody vehicle and comprising a casing and a member movable fitted in thecasing separating the latter into the upper and lower chambers, a sourceof compressed fluid for the casing, a valve controlling the admittanceof the iiuid into the chambers of the casing, and consisting of tworelatively movable parts, yieldable means to keep the rst valve part inthe neutral position, yieldable means to keep the second valve part inthe neutral position, elements responsive to the velocity and/oracceleration of the body in directions transverse to the progressivemovement of the vehicle, means to move the rst valve part by saidelements for admitting compressed fluid into and the axle of a onechamber while exhausting the fluid, from the y other chamber so as tooppose said transverse movements of the body, and means to move thesecond valve part into the neutral position by the diierential pressurein the chambers.

12. A valve for controlling differential pressure the compressed uidinto one of the chambers, until the rst valve closes the second valveunder action of said differential pressure.

13. A shock absorber and stabilizer comprising a motor adapted to besupported between the body and the end portion of the axle of a vehicle,a source of power for the motor, elements responsive to dynamiccharacteristics of the vertical movements of the body, means responsiveto horizontal movements of the body in direction outward from said endportion of the axle', and means to control power input for the motor bysaid elements so as to create torque in the motor opposing saidmovements.

14. A shock absorber and stabilizer comprising a motor adapted to besupported between the body and the end portion oi' the axle of avehicle, a source of power for the motor, a vertically movable elementresponsive to dynamic characteristics of the vertical movements of thebody, a hinged vertically movable element responsive dynamiccharacteristics of horizontal movements of the body in direction outwardfrom said end portion of the axle and means to control power input forthe motor by said elements so as to create torque in the motor opposingsaid movements.

15. A shock absorber and stabilizer for a body comprising a motorelement responsive to absolute velocities of the body in selecteddirections comprising a container with a viscous fluid, a flexiblemember closing. the container, a weight supported on the ilexiblemember, and adapted to exert pressure on the uid, a cylinder in arestricted communication with the fluid, a member movably supported inthe cylinder, retrieving means for balancing the normal fluid pressureon the member, the travel of the member being therefore substantiallyproportional to the velocity of the body in said selected directions,and means to control the motor by the movable member.

' 16. A shock absorber andy stabilizer for a body comprising a motor, anelement responsive to absolute acceleration of the body in selected 17.A shock absorber and stabuizerfor a body resiliently supported von amember contacting a supporting medium, the body and the member beingadapted to have a motion of translation over the supporting medium, thebody ybeing adapted to have oscillatory movements in relation to thesupporting member in direction transverse to the motion of translation,a uid motor interposed between the body and the member, and consistingof a casing with a plunger movably fitted in the casing and separatingthe casing into the upper and lower chambers, a source of compressed uidfor the motor, a valve adapted to control the admittance of the uid intoone of `the chambers while exhausting the fluid from the other. chamber,a movable element in the casing responsive to the velocity of thetransverse motion of the body, a movable element in the casingresponsive to the inertia` of the body in its transverse movement, meansto operate the valve by said movable elements so as to oppose thetransverse 'movements of the body while assisting movements of thesupporting member, and means to neutralize the action of the valve bythe diiferential pressure in the chambers, an auxiliary fluid motoropposing movement of said elements, and means to control the auxiliarymotor by the position of the plunger in the casing, said meansconsisting of a valve adapted to control admission of the compressed ofthe transverse movement of the body, and

fluid to the auxiliary motor, a spring pressing on the valve, means tovary, the spring tension by the position of the plunger in the casing,the

valve being adapted to be balanced by the fluid pressure in theauxiliary motor acting on the valve in direction opposite to the springpressure.

18. A fluid pressure relay comprising a casing and a member movableiitted in casing separating the latter into upper and lower chambers,

actuate the valve, movable means responsive to pressure conditions inthe chambers, a dampening device restraining the movement of movablemeans, and controlling r,means for the valve responsive to conditions ofmovement of the body.l

19. A fluid pressure relay comprising a casing and a member movablefitted in casing separating the latter into upper and lower chambers, asource of compressed fluid for the casing, a valve controlling theadmission of the iiuid into chambers of the casing, movable means toplace the valve into neutral position, a cam actuated by the movement ofthe member, an operative connection between the cam and movable means,and controlling means for the valve responsive to the movements of thebody.

20. A yieldable uid pressure support for a body over a member contactinga supporting medium, the body and the member being adapted i to have amotion of translation oggi/er thesupporting medium, comprising a iiuidmotor interposed between the body and the member, a source of compressediiuid for the motor, a valve controlling the distribution of the uid tothe motor, a movable element responsive to the change of distancebetween the body and the member, and means to move the valve by themovableelement so as to oppose the transverse movements of the body bythe motor, and means to return the valve into the neutral position bythe differential iiuid pressure in the motor;

21. A shock absorber and stabilizer for a body resiliently supported ona member contacting a supporting medium, comprising a motor interposedbetween the body and the member, a source of power for the motor on thebody, the body of translation on the supporting medium, a movableelement adapted to control the power for 'the motor, elements responsiveto the velocity and acceleration of the body in relation to thesupporting member, and means to control the movable element by saidelements so as to cause the motor toresist the movements of the body inrelation to tlie supportifng member.

V22. A shock absorber for a body resiliently supported on a membercontacting a supporting medium, the body and the member being adapted tohave a motion of translation over the supporting medium, a uid motorinterposed between the body and the member, a source of fluid for themotor, a two-part compound movable valve for controlling communicationbetween the motor and the source of fluid, means to move one part of thecompound valve a relatively large distance proportional to thediierential pressure between the compression and suction sides of themotor for relieving pressure of the fluid in the compression side,suction operated means for admitting uid into the suction side, amovable inertia element responsive to dynamic properties means to movethe second part of the compound valve by the inertia element arelatively large distance proportional to a combination of dynamicproperties of the transverse movement of the body for stabilizing thetransverse movement of the body by the fluid pressure built up in and bythe motor.

23. A shock absorber for a body'resiliently supported on a membercontacting a supporting With the member being adapted to have a motionmedium, the body and the member being adapted to have a. motion oftranslation over the supporting medium, a fluid motor interposed betweenthe body and the member, a source of fluid for the motor, a valve forcontrolling communication between the motor and the source of uid, amovable inertia element responsive to dynamic properties of thetransverse movements of the body, means to move the valve by the inertiaelement a relatively large distance for opposing by the ud pressure inthe motor the transverse movements of the body, and means to move thevalve toward its neutral position a relatively large distanceproportional to the differential pressure of the fluid in thecompression and suction sides of the motor.

SERGEI D. MITEREFF.

